Camera

Claim 2

A camera system according to claim 1, wherein said correction means is arranged to correct said aperture information obtained by said detecting means by using data stored in a memory.

Claim 3

A camera system according to claim 1, wherein said optical accessory is mounted between said camera body and said interchangeable lens.

Claim 4

A camera system according to claim 1, further comprising a focus control circuit arranged to operate by using said aperture information.

Claim 5

A camera system according to claim 1, further comprising second detecting means for detecting the kind of said optical accessory.

Claim 6

A camera system according to claim 5, wherein said correction means is arranged to vary a correction value to be used in correcting said aperture information according to the result of detection made by said second detecting means.

Claim 7

A camera system according to claim 1, wherein said correction means is disposed within said interchangeable lens.

Claim 8

A camera system according to claim 1, wherein said correction means is disposed within said optical accessory.

Claim 9

A camera system according to claim 1, wherein said optical accessory is a telephoto conversion lens.

Claim 10

A camera system according to claim 5, wherein said second detecting means is arranged to detect also mounting or nonmounting of said optical accessory.

Claim 11

A camera system according to claim 5, wherein said second detecting means is arranged to detect the kind of said optical accessory on the basis of voltage information.

Claim 12

A camera system according to claim 10, wherein said second detecting means is arranged to detect mounting or nonmounting of said optical accessory and the kind of said optical accessory on the basis of voltage information.

Claim 13

A camera system according to claim 5, wherein said interchangeable lens is provided with an electrical contact exclusively used for detecting the kind of said optical accessory.

Claim 14

A camera system according to claim 10, wherein said interchangeable lens is provided with an electrical contact exclusively used for detecting mounting or nonmounting of said optical accessory and the kind of said optical accessory.

Claim 15

A camera system having at least a camera body and an interchangeable lens, comprising: A) said camera body, including: A-1) focusing means for controlling focus by taking into consideration aperture information supplied from said interchangeable lens; and A-2) a first contact provided for communication with said interchangeable lens; and B) said interchangeable lens, including: B-1) a diaphragm having a variable aperture; B-2) detecting means for detecting aperture information obtained by stopping down said diaphragm; B-3) a second contact provided for communication with said camera body; B-4) a third contact provided for detection of mounting of an optical accessory; and B-5) a correction circuit arranged to correct said aperture information obtained by said detecting means when mounting of said optical accessory has been detected through information from said third contact, and to supply the corrected aperture information via said second contact to said camera body.

Claim 16

A camera system according to claim 15, wherein said correction circuit is arranged to correct said aperture information by using data stored in a memory.

Claim 17

A camera system according to claim 15, wherein said optical accessory is disposed between said camera body and said interchangeable lens.

Claim 18

A camera system according to claim 15, wherein said correction circuit is arranged to detect also the kind of said optical accessory through information from said third contact and to correct said aperture information in accordance with the kind thus detected.

Claim 19

A camera system according to claim 17, wherein, when said interchangeable lens is mounted on said camera body, said first contact is in contact with said second contact and said third contact is not in contact with said first contact.

Claim 20

A camera system according to claim 17, wherein, when said optical accessory is mounted between said camera body and said interchangeable lens, said first contact is in contact with a fourth contact provided on said optical accessory, said second contact is in contact with a fifth contact provided on said optical accessory, and said third contact is in contact with a sixth contact provided on said optical accessory.

Claim 21

A camera system according to claim 20, wherein said fourth and fifth contacts provided on said optical accessory are interconnected with each other, and said sixth contact is connected to an information supply circuit arranged to supply information on said optical accessory.

Claim 22

A camera system according to claim 20, wherein said fourth and fifth contacts provided on said optical accessory are interconnected with each other, and said sixth contact is connected to an information supply circuit arranged to supply information on the kind of said optical accessory.

Claim 23

A camera system according to claim 21, wherein said information supply circuit is arranged to supply said information in the form of a voltage.

Claim 24

A camera system according to claim 22, wherein said information supply circuit is arranged to supply said information in the form of a voltage.

Claim 25

A camera system according to claim 22, wherein said correction circuit is arranged to detect also the kind of said optical accessory through information from said third contact and to correct said aperture information in accordance with the kind thus detected.

Claim 26

A camera system according to claim 20, wherein said optical accessory is a telephoto conversion lens.

Claim 27

An optical accessory capable of being mounted between an interchangeable lens and a camera body, comprising: a correction circuit arranged to correct aperture information obtained by stopping down a diaphragm in said interchangeable lens, and to supply the corrected aperture information to said camera body.

Claim 28

An optical accessory according to claim 27, wherein said correction circuit is arranged to correct said aperture information by using data stored in a memory.

Claim 29

An optical accessory according to claim 27, wherein said optical accessory is a telephoto conversion lens.

Claim 30

An interchangeable lens capable of being mounted on a camera body and capable of mounting an optical accessory thereon, comprising: a) first detecting means for detecting mounting of said optical accessory; b) a diaphragm having a variable aperture; c) second detecting means for detecting aperture information obtained by stopping down said diaphragm; and d) a correction circuit arranged to correct said aperture information obtained by said second detecting means when mounting of said optical accessory has been detected by said first detecting means.

Claim 31

An interchangeable lens according to claim 30, wherein said interchangeable lens is a zoom lens, and said aperture information on said diaphragm varies according to a change of the zoom ratio of said zoom lens.

Claim 32

An interchangeable lens according to claim 30, wherein said correction circuit is arranged to correct said aperture information by using data stored in a memory.

Claim 33

An interchangeable lens according to claim 31, wherein said correction circuit is arranged to correct said aperture information by using stored data every time the zoom ratio of said lens changes.

Claim 34

An interchangeable lens according to claim 30, wherein said first detecting means is arranged to detect not only mounting of said optical accessory but also the kind of said optical accessory mounted.

Claim 35

An interchangeable lens according to claim 34, wherein said correction circuit is arranged to correct said aperture information according to the kind of said optical accessory mounted.

Claim 36

An interchangeable lens according to claim 35, wherein said correction circuit is arranged to correct said aperture informaiton according to the kind of said optical accessory on the basis of stored data.

Claim 37

An interchangeable lens according to claim 30, wherein said first detecting means is arranged to detect mounting or nonmounting of said optical accessory on the basis of voltage information.

Claim 38

An interchangeable lens according to claim 34, wherein said first detecting means is arranged to detect mounting or nonmounting of said optical accessory and the kind of said optical accessory on the basis of voltage information.

Claim 39

An interchangeable lens according to claim 30, wherein said first detecting means includes an electrical contact exclusively used for detection of mounting of said optical accessory.

Claim 40

An interchangeable lens according to claim 34, wherein said first detecting means includes an electrical contact exclusively used for detection of mounting or nonmounting of said optical accessory and the kind of said optical accessory.